ci: Makefile: Mention CI_MAKE_ARGS and CI_CONFIGURE_ARGS in ci-help

Document the CI_MAKE_ARGS and CI_CONFIGURE_ARGS so that users don't have
to skim through the Makefile to be able to pass arbitrary recognized
make targets to the build system.
Signed-off-by: NErik Skultety <eskultet@redhat.com>
Reviewed-by: NAndrea Bolognani <abologna@redhat.com>

ci/Makefile

@@ -263,7 +263,9 @@ ci-help:
 	@echo
 	@echo "Available make variables:"
 	@echo
-	@echo "    CI_CLEAN=0     - do not delete '$(CI_SCRATCHDIR)' after completion"
-	@echo "    CI_REUSE=1     - re-use existing '$(CI_SCRATCHDIR)' content"
-	@echo "    CI_ENGINE=auto - container engine to use (podman, docker)"
+	@echo "    CI_CLEAN=0          - do not delete '$(CI_SCRATCHDIR)' after completion"
+	@echo "    CI_REUSE=1          - re-use existing '$(CI_SCRATCHDIR)' content"
+	@echo "    CI_ENGINE=auto      - container engine to use (podman, docker)"
+	@echo "    CI_CONFIGURE_ARGS=  - extra arguments passed to configure"
+	@echo "    CI_MAKE_ARGS=       - extra arguments passed to make, e.g. space delimited list of targets"
 	@echo